The reaction 26Mg(p,γ)27Al : (II). Spins of 27Al levels

Abstract

Measurements of double and triple angular correlations and gamma-ray polarizations at twenty resonances in the reaction 26Mg(p, γ)27Al, lead to the unambiguous spin and panty assignments J[pi]=7+/2,5+/2, 3+/2,9+/2 and 5/2 to the bound states of 27Al at 2 21, 2.73, 2.98, 3.00 and 4.81 MeV, respectively. The 6.48 MeV level has J= 7/2(5/2). The quadrupole/dipole amplitude mixing ratios of the gamma rays de-exciting these levels are given.The spins of 15 resonance levels and the mixing ratios of the mare branches in the resonance decay also follow from this experiment. The combined evidence of the decay of the resonance levels and bound states leads to suggested spmvalues J= (½,3/2), 3/2 (1/2, 3/2), 5/2,5/2, (3/2, 5/2, (3/2,5/2), 3/2,3/2,3/2 and 3/2 for 27Al* = 3.68, 3.96, 4.05, 4.41, 5.25, 6.11, 6.16, 6.61, 6.65 and 6.78 MeV, respectively.